Electromagnetic switch



Dec. 15, 1936. R. H. SCHMITT 2,064,632

ELECTROMAGNETIC SWITCH Filed Sept. 26, 1935 hull R MWW 1 :l

Inventor:

Richard Hfs hrnitt by 7vmngi wLw Hi Attoi neg.

Patented Dec. 15, 1936 UNITED STATES PATENT OFFICE- EIECTROMAGNETICswrrcn Richard H. Schmitt, Schenectady, N. Y., assignor to GeneralElectric Company, a corporation of a New York Application September 26,1935, Serial No. 42,267

19' Claims.

My invention relates to electromagnetic devices, more particularly toelectromagnetically operated, multiple pole switches or contactors, andhas for an object the provision of a simple, reliable, and inexpensivedevice of this character.

Heretofore, various types of multiple pole electromagnetic switches havebeen provided, all of which are to a large extent satisfactory for thepurposes intended. Much is yet to be desired, however, in switches ofthis type, which are of small size, which are inexpensive to constructand which are reliable and economical in their operation. Furthermore,it is desirable that switches of this type be highly flexible in theirapplication, being readily convertible from normally open to normallyclosed devices and being readily convertible to provide a diiferentnumber of poles. Accordingly, it is a further object of my invention toprovide an electromag! netically operated, multiple pole switch which issimple and inexpensive to construct and which has a high degree ofreliability in its operation, together with a high degree of flexibilityin its application.

In carrying out my invention in one form, I provide an electromagneticswitch comprising an operating bar mounted for reciprocal movementtransversely of its axis to operate between open and closed, circuitpositions, a plurality of pairs of relatively movable switch memberswhich are disposed along the bar. A plurality of symmetrical insulatingbarriers are arranged to form individual arcing chambersfor each pair ofswitch members, and electromagnetic means are provided for moving theoperating bar transversely to operate the switch members.

More specifically, the electromagnetic operating means comprises astationary magnetic member mounted on a frame between a pair ofspaced-apart plates and a pair of elongate members or push rods, one ofwhich is arranged ad- .iacent each plate. Means are provided for sup-'portinaand guiding each of the push rods for longitudinal movement alongthe plates, and a movable magnetic member is supported on the c' ac ntends of the push rods in co-operating relation with the stationarymagnetic member. The opposite end of each of the push rods is secured toone of two grooved blocks which are respectively slidable over the endsof the operating bar, the two grooved. blocks serving t support the barintermediate its ends. Each of the symmetrical insulating barriers isprovided with similar proiecting portion: on its opposite faces, and apair of arms extending from the frame of the switch are provided forsupporting the barriers adjacent the operating bar in face-to-facerelation with each other, so

' that the projecting portions on each barrier en- 5 'bers for operationby the operating bar.

For a more complete understanding of my invention, reference should nowbe had to the drawing, in which Fig. 1 is an elevational view of anelectromagnetic switch embodying my invention; Fig. 2 is an end view ofthe switch 15 shown in Fig. 1; Fig. 3 is a fragmentary sectional viewtaken through the center of one of the arcing chambers, the contactstructure being shown in elevation; Fig. 4 is -a perspective view of oneof the symmetrical insulating barriers 20 embodying my invention; Fig. 5.is a fragmentary sectional view taken along the line 5-5 of Fig.

l; and Fig. 6 is a sectional view similar to Fig. 3, illustrating amodified form of my invention.

Referring now to Figs. 1 to 5, inclusive, of '25 the drawing, incarrying out my invention in one form, I provide an electromagneticswitch I0 comprising a frame having a pair of spacedapart plates II andI2 connected adjacent their ends by a. pair of cross members l3 and H.As 30 shown, the cross member i3 is bowed out slightly from the plates Ii and I2, and the cross member I4 is provided with an extending ear i5.As will be apparent from the description which follows, the entireelectromagnetic switch is supported by the frame comprising the plates-H and I2, and accordingly, no subbase is necessary, the cross member 13and the ear I: serving to support the electromagnetic switch directlyupon a panelboard or the frame of a machine. Mounted between the platesIll and II, I provide an operating electromagnet comprising an E-shapedstationary magnetic member it, an energizing winding l1, and a movableE-shaped magnetic member It. The stationary magnetic member i6 ismounted on the frame by a single screw I! which is arranged tothreadedly engage an ear (not shown) which extends outwardly irom thecross member I. This screw I! also serves to secure to the stationarymagnetic member it a pair of spring arms 20, only one of which is shown,which spring arms resiliently support the energizing winding H on themiddle leg of the E-shaped magnetic member it. As shown best in Fig. 2,the ends of the spring arms opposite from the screw l9 are bentoutwardly and engage an insulating disk 2| which supports the energizingwinding As shown, the movable magnetic member H! is supported inco-operating relation with the stationary magnetic member I6 and theenergizing winding H by a pair of elongate members or push rods 22, oneof which is arranged adjacent each of the plates and'|2. Both thestationary magnetic member I6 and the movable magnetic member l8 are oflaminated construction for alternating-current operation, and aplurality of the laminations of the movable magnetic member I8 extendoutwardly from opposite sides thereof to form supporting ears 23arranged to engage co-operating notches 24 formed in the push rods 22.Each of the push rods 22 is provided with an elongate slot 25, the slot25 in one of the push rods co-operating with a finger 26 extending fromthe plate I l, and the slot '25 the other push rod co-operating with afinger 2? extending from the plate 12. The slots 25 and the fingers 26and 2'5 co-operate to guide the push rods 22 for longitudinal movementalong the plates H and 2, and as shown best in Fig. 2, the upper end ofeach of the push rods 22 is provided with an extending ear 28. It willbe understood of course that the movable magnetic member l8 and the pushrods 22 are biased by gravity to the lowermost position shown in thedrawing, the extending ears 28 on the push rods 22 engaging the upperedges of the plates H and i2, as shown best in Fig. 2, to provide stops.

The push rods 22 support the movable contact structure of the switch,which contact structure comprises a plurality of movable contacts 29resiliently supported, as shown best in Fig. l, on an operating bar 30.This operating bar 30 is provided at its opposite ends with portions ofreduced width so as to form shoulders 3| thereon, and a pair of groovedinsulating blocks 32 which are slidable over the reduced ends of the bar3|] into engagement with the shoulders 3| serve to support the barintermediate its ends. As shown best in Fig. 2, these grooved blocks 32are secured to the ears 28 on the push rods 22 by means of suitablescrews 33. It will thus be seen that when the push rods 22 are movedlongitudinally along the plates II and 2 upon energization of thewinding l1, the operating bar 30 and the movable contacts 29 carriedthereby will be moved upwardly.

As shown best in Figs. 1 and 3, each of the movable contacts 29 isresiliently supported by a spring 34 which normally biases the contact29 into engagement with a washer 35 on the end of a guide post 36 whichslidably extends through an aperture, not shown, in the contact member29. The lower end of the springs 34 bear against the operating bar 30,and the posts 36 are secured to the bar 30 by means of screws 31 (Fig.2) which extend through the bar. As shown in Fig. 2, the screws 31 areinsulated from other metallic parts of the electromagnetic switch bymeans of a strip of insulating material 38 which extends along the lowerside of the bar 30 and is held in place by the grooved blocks 32.Suitable cylindrical guides 39, formed of insulating material, areprovided for each of the springs 34.

Arranged adjacent the movable contact members 29. I provide a pluralityof pairs of spacedapart fixed contacts 40 which are carried by suitab econductor bars 4|, the conductor bars which extend through the apertures45.

riers 42 are preferably formed of molded insulation material and, asshown in Fig. 4, the opposite faces of eachbarrier are provided with aplurality of projecting portions 43, 44, and 45 and with a pair ofapertures 46, which apertures extend through the barrier between itsopposite faces.

As shown, a plurality of these insulating barriers 42 are supported inface-to-face relation with each other adjacent the movable contacts 29by means of a pair of supporting rods 41,

The opposite ends of these rods 41 are supported by a pair of arms 48extending upwardly from the spaced plates II and |2, the lower ends ofthe arms 48 being secured to the plates II and H by suitable screws 49.As shown in Fig. 3, the rods 4'! are surrounded by tubular insulatingmembers 50 so as to prevent arcing between the adjacent poles of theswitch.

It will be apparent that when the insulating barriers 42 are assembledin face-to-face rela tion, the projecting portions 43, 44, and 45 oneach barrier will engage similar projecting portions on the nextadjacent barriers so as to form partially enclosing arcing chamberstherebetween within each of which a pair of the relatively movablecontacts 29 and 40 is adapted is: engage and disengage each other, thecontacts 13 being movable through an open side of the arcing chamber.Thus, any are drawn between the contacts 29 and 40 will be confined bythe arcing chamber so as to prevent flashover between the adjacent polesof the switch.

Although the stationary contacts 40 may be mounted in any suitablemanner within the arcing chambers formed by the insulating barriers 42,I prefer to provide the projections 43 and 45 on the insulating barriers42 with semicircular grooves 5|, and to provide suitable fasteningmeans, such as the screws 52, which extend through the apertures thatare formed by the grooves 5| when the barriers 42 are assembled inface-to-face relation. As shown best in Fig. 3, these screws 52 engagethe conductor bars 4| on which the stationary contacts 40 are mounted,and the opposite ends of the conductor bars 4| which extend outwardlyfrom the arcing chamber formed by the projections 43, 44, and 45 areprovided with suitable terminal screws 53.

As shown, the projections 43, 44, and 45 are spaced inwardly from theouter edges of the barriers 42, and accordingly, when the barriers 42are assembled in face-to-face relation, a plurality of parallel groovesare formed within which the outer ends of the conductor bars 4| and theterminal screws 53 are entirely disposed. That is, the terminal screws53 and the conductor bars 4| do not extend outwardly beyond the edges ofthe barriers 42, and accordingly, the barriers protect these membersfrom damage due to accidental blows. Likewise, a uniform outline and apleasing appearance of the electromagnetic switch H) are obtained.

In order that the energizing winding may be conveniently connected in acontrol circuit, I provide a terminal block 54 formed of insulatingmaterial, which block is secured to the plate I2 and carries a pair ofterminal plates 55 to which the lead wires 56 of the coil H areconnected. The terminals 53 extend upwardly from the arcing chambersformed by the insulating barriers 42 and are readily accessible forconnection in 2,064,682 any suitable circuit or circuits to becontrolled. I

It will be apparent now, that when the winding I1 is energized, themovable magnetic element l8 will be attracted toward the stationarymagentic element l6, thereby operating the push rods 22 and theoperating bar 30 to move thecontacts from the open circuit positionshown in Figs. 1, 2, and 3 to a closed circuit position in which thecontacts 29 engage the contacts 40.

Disassembly of my improved switch for purposes of inspection may beaccomplished simply by removing the screw i9, whereupon the magneticelements i6 and I8 and the energizing winding Il may be removed as aunit, the leads 56 having been disconnected, without disturbing theremaining parts of the switch. The push rods 22 may thereafter bepressed inwardly until the slots 25 are free of the fingers 26 and 31,whereupon the push rods 22, the blocks 32 and the bar 30 with themovable contacts 29 thereon may be removed as a unit from the frame.Inspection of the stationary contacts 40 may be made through the openlower side of the arcing chambers, and disassembly oi the arcingchambers for replacement of the contacts or the insulating barriers maybe accomplished simply by withdrawing the rods 41.

It will be apparent now that switches embodying my invention are simplein construction and may be readily assembled and disassembled. Likewise,it will be seen that the switch in may be converted into a switch havinga greater or a less number of poles by providing suitably shapedsupporting arms 48 for supporting any desired number of insulatingbarriers and by providing an operating bar 30 having the desired numberof movablecontacts thereon.

The switch shown in Figs. 1 to 5, inclusive, is of the normally opentype. It is sometimes desirable to utilize a normally closed switch or amultiple pole switch having certain poles normally closed and certainother polesnormally open, and accordingly, I have shown in Fig. 6 anormally closed switch embodying my invention.

Referring to Fig. 6, suitable stationary con,- tacts 51 are mounted onconductor bars 58 within thearcing chamber formed by the barriers 42.These conductor bars 58 are similar to, but

somewhat longer than, the conductor bars 4| shown in Fig. 2. In thistype of switch, the contacts 51 are secured to the upper side of theconductor bars 58 as viewed in the drawing, and a movable contact member59 is normally biased into engagement with the contacts 51. by a spring60 which surrounds a guide post 6i, one end of which slidably extendsthrough the contact member 59. As shown, the other end of the post 6| issupported by the projecting portion 44 on the barrier '42, each of thebarriers being provided with a semicircular groove 52 which is similarto the grooves 5| in the projecting portions 43 and 45. The semicirculargroove 62 is provided with an enlarged portion 53, which be operated asdescribed in connection with Figs. 1 to 5, and the contact 59 will bemoved against its bias to open the circuit between the fixed contacts51.

Switches embodying my invention may thus be provided with a plurality ofnormally openv contacts, with a plurality of normally closed contacts,or with a combination of normally open will be apparent that switchesembodying my invention are very flexible in their operation.

While I have shown a particular embodiment of my invention, it will beunderstood, of course, that I do not wish to be limited thereto sincemany modifications may be ade, a d I, therefore, contemplate by theappended claims to cover any such modifications as fall within the truespirit and scope of my invention. I 7

What I claim as new and desire to secure by Letters Patent of the UnitedStates, is:

1. An electromagnetic device comprising a frame having a pair ofspaced-apart plates, 2. pair of elongate movable members'each of whichis arranged adjacent one of said plates, guide means associated witheach plate and each movable member for supporting and guiding saidmembers for longitudinal movement relative to said plates, means formoving said members longitudinally of said plates including a stationarymagnetic element mounted on said frame between said plates and a movablemagnetic element supported on adjacent ends of said elongate members incooperating relation with said stationary element, and control meanssupported on the adjacent-ends of said elongate members opposite fromsaid movable magnetic element.

2. An electromagnetic device comprising a frame having a pair of spacedapart plates, a pair of elongate movable members each of which isarranged adjacent one of said plates, guide means associated with eachplate and each movable member for supporting and guiding said magneticmember.

3. An electromagnetic dvice comprising a frame having a pair of spacedapart plates, a pair of elongate members each 01' which is arrangedadjacent one of said plates and provided with a notch adjacent one end,guide means associated with each plate and the adjacent mov-- ablemember for supporting and guiding said members for movement along saidplates, means for moving saidmembers along said plates inand normallyclosed contacts. Accordingly, it

eluding a stationary magnetic member mounted control means operable bymovement of said elongate members along said plates.

4. An electromagnetic device comprising a frame having a pair of spacedapart plates, a

pair of elongate movable members each of which is arranged adjacent oneof said plates and provided with a notch adjacent one end, guide meansassociated with each plate and the adjacent movable member forsupporting and guiding said members for movement along said plates,means for moving said members along said plates including a stationarylaminated magnetic member mounted on said frame between said plates anda movable laminated magnetic member, a plurality of laminations of saidmovable magn tic member having outwardly projecting portions formingsupporting ears on opposite sides of said member, said ears cooperatingwith said notches to support said movable magnetic member b tween saidelongate members, and control means operable by movement of saidelongate members.

5. An electromagnetic device comprising a frame having a pair of spacedapart plates each of which is provided with a laterally extendingfinger, a pair of movable members each of which arranged adjacent one ofsaid plates and provided wi h an elongate slot for cooperating with thefinger extending from the adjacent plate whereby said members are guidedfor movement along said plates, means for moving said members along saidplates including a stationary magnetic element mounted on said framebetween said plates and a movable magnetic element supported on adjacentends of said movable members, and control :means supported on theadjacent ends of said movable members opposite i from said movablemagnetic element.

5.1m electromagnetic device comprising a of which is provided with aninwardly extending finger, a pair of elongate push rods between saidplates each of which is arranged adjacent one of said plates andprovided with an elongate slot for cooperating with the finger extendingfrom the adjacent plate to guide said rods for movement along saidplates. means for moving said along said plates comprising magneticstructure including a stationary E-shaped magnet mounted on said framebetween said rods and a movable E-shaped magnet supported by said rodsspaced relation to said stationary magnet, means for energizing saidmagnetic structure to attract said movable magnet and move said redsalong said plates, and control means supported on the adjacent ends ofsaid rods opposite frcni said movable magnet.

7. An electromagnetic device comprising an operating bar, a pair ofsupporting blocks having grooves therein, said blocks being respectivelyslidable onto opposite ends of said bar for supporting said barintermediate its ends, a pair of push rods one of which is secured toeach of said blocks, electromagnetic means for moving said push rods tomove said operating bar transversely of its axis, and control meansspaced along said bar for operation thereby.

8. An electromagnetic device comprising an operating bar having reducedends so as to form spaced apart shoulders on said bar intermediate saidends, a pair of grooved blocks respectively slidable over said reducedends into engagement with said shoulders for supporting said bar, a pairof push rods respectively secured to said blocks, means for guiding saidrods for movement to operate said bar transversely of its axis,electromagnetic means for moving said rods, and control means spacedalong said bar for operation thereby.

'9. An electromagnetic device comprising an operating bar having reducedends forming spaced apart shoulders on said bar intermediate said ends,a pair of grooved blocks respectively slidable over said reduced endsinto engagement with said shoulders for supporting said bar, a pair ofsubstantially parallel, elongate operating members respectively securedto said blocks, a frame having a pair of spaced apart plates adjacentsaid operating members, guide means associated with said plates and saidembers for guiding said members for longitudinal movement along saidplates, electromagnetic means mounted between said plates and includinga movable element for operating said members to move said bartransversely of its axis, and a plurality of control means spaced alongsaid bar for simultaneous operation thereby.

10. An electromagnetic device comprising an operating bar, a pair ofgrooved blocks respec tively slidable over the ends of said bar forsupporting said bar, means for positioning said blocks on said bar, apair of push rods respectively connected to said blocks and extendingoutwardly therefrom in substantially parallel relation, a framecomprising a pair of spaced apart plates respectively adjacent said pushrods, guide means associated with each plate and the adjacent rod forguiding said rods for movement along said plates, electromagnetic meansfor moving said rods including a stationary magnetic member mounted onsaid frame between said plates and a movable magnetic member supportedin cooperating relation with said stationary magnetic member on the endsof said rods remote from said blocks, and a plurality of switch membersspaced along said bar for operation thereby.

11. An electric switch comprising a plurality of symmetrical insulatingbarriers each of which is provided with a plurality of spaced, similaroutwardly projecting portions on opposite sides thereof, means forsupporting said barriers in face-to-face relation, said projectingportions on each barrier engaging similar projecting portions on thenext adjacent barriers to form arcing chambers therebetween, the spacesbetween said projecting portions forming apertures in the walls of saidarcing chambers, contact members movable relative to each other betweenopen and closed circuit positions within each arcing chamber and meansextending through said apertures for supporting certain of saidcontacts.

12. An electric switch comprising a plurality of symmetrical insulatingbarriers each of which is provided with a plurality of similar, spacedprojecting portions on opposite sides thereof and with an apertureextending thereth'rough transversely to said opposite faces, fasteningmeans including an insulated rod extending through said apertures forsecuring said barriers together in face-to-face relation, saidprojecting portion: on each barrier engaging similar projections on thenext adjacent barriers to form arcing chambers therebetween, the spacesbetween said projecting portions forming apertures in the walls of saidarcing chambers, contact members movable relative to each other betweenopen and closed circuit positions within each arcing chamber andconductor means extending through said apertures in said chamber wallsfor supporting certain of said contacts.

13. An electric switch comprising a plurality of symmetrical insulatingbarriers each 01' which is provided with similar outwardly projectingportions on opposite faces thereof, means for supporting said barriersin face-to-iace relation,

said projecting portions on each barrier enming similar projections onthe next adjacent barriers to form therebetween arcing chambers havingat least one open side, stationary contact means supported within eachof said chambers, movable contact means operable into and out ofengagement with said stationary contact means, and means extendingthrough said open side of each of said chambers for operating saidmovable contact means.

14. An electric switch comprising a plurality of symmetrical insulatingbarriers each of which is provided with similar outwardly projectingportions on opposite faces thereof, means for supporting said barriersin face-to-face relation, said projecting portions on each barrier.engaging similar projections on the next adjacent barriers to formtherebetween arcing chambers having at least one open side, stationarycontact means supported within each of said chambers, movable contactmeans supported within each of said chambers and normally biased intoengagement with said'stationary contact means, and means extendingthrough said open side of each of said chambers for operating saidmovable contact means out of engagement with said stationary contactmeans.

'15. An electric switch comprising a plurality of symmetrical insulatingbarriers each of which is provided with similar outwardly projectingportions on opposite faces thereof, means for supporting said barriersin face-to-face relation, said projecting portions on each barrierengaging similar projections on the next adjacent barriers to formtherebetween arcing chambers having at least one open side, stationarycontact means supported within each of said chambers, and movablecontact means associated with each of said chambers operable into andout of said chambers through said open side selectively to engage anddisengage said stationary contact means.

16. An electric switch comprising a plurality of symmetrical insulatingbarriers each of which is provided with similar outwardly projectingportions on opposite sides thereof, at least one of said similarprojecting portions on each side of said barrier having a groove in theface thereof, means for supporting said barriers in face-to-facerelation, said projecting portions on each barrier engaging similarprojecting portions on the next adjacent barriers to form arcingchambers therebetween, said grooves in said projecting portionscooperating to form an aperture through a; wall of each of said arcingchambers,

contact members disposed within said arcing chambers, and meansincluding a member extendingthrough said aperture for supporting certainof said contact members.

17. An electromagnetic switch comprising a frame having a pair of spacedapart plates, a pair of elongate movable members each of which isarrangedv adjacent one of said plates, guide means associated with eachplate and each movable member for supporting and guiding said members atlongitudinal movement relative to said plates, means for moving saidmembers longitudinally including a stationary magnetic member mounted onsaid frame between said plates and a movable magnetic member supportedon adjacent ends of said elongate members in cooperating relation withsaid station-. ary magnetic member, an operating bar, means -forsupporting said operating bar on the adjacent ends of said elongatemembers opposite from said movable magnetic member, a plurality ofswitch means spaced along said operating bar for operation therebybetween open and closed circuit positions when said elongate members aremoved longitudinally, a pair of supporting arms extending from saidframe, and a plurality of symmetrical insulating barriers supported bysaid arms in face-to-face relation with each other, each of saidbarriers having similar outwardly projecting portions on opposite facesthereof arranged to engage similar projecting portions on the nextadjacent barriers to form therebetween individual arcing chambers foreach of said switch means.

18. In an electric switch, the combinationof a 'plurality of symmetricalinsulating barriers each of which is provided with similar projectingportions on opposite faces thereof, means for supporting said barriersin face-to-iface relation, said projecting port-ions on each barrierengaging similar projecting portions on the next adjacent barriers toform arcing chambers therebetween, said projecting portions being spacedinwardly from theedges of said barriers and forming in conjunctiontherewith a plurality of grooves surrounding said arcing chambers.contacts supported within each of said arcing chambers and terminalmembers arranged in said grooves and connected to associated ones ofsaid contact members, the depth of said grooves being such that saidterminal members are entirely disposed therewithin.

19. In an electric switch, the combination of a plurality of symmetricalinsulating barriers each of which is provided with similar projectingportions on opposite faces thereof, means for supporting said barriersin face-to-iace relation, said projecting portions 'on each barrierengaging similar projecting portions on the next adjacent barriers toform arcing chambers therebetween, said projecting portions being spacedinwardly from the edges of said barriers to form in conjunctiontherewith a plurality of that said terminal members are entiretydisposed therewithin.

RICHARD H,

